Surgical versus medical therapy of hypertrophic cardiomyopathy: is the perspective changing?

Coronary Morphology and Conduction System Disturbance Induced by Therapeutic Embolization of the Coronary Septal Artery

Background: Percutaneous transluminal septal myocardial alcohol ablation (PTSMAA) is not a procedure without complications. It may produce heart arrhythmias, especially those due to disturbances of atrioventricular (AV) and interventricular (IV) electrical conduction.Objective: The goal of this study was to evaluate the relationship between the anatomical patterns of the right coronary artery and the left anterior descending artery (LAD) and to relate them to the AV and IV bundle branch blocks provoked by PTSMAA.Method: Twenty patients with obstructive hypertrophic cardiomyopathy resistant to treatment with drugs successfully underwent PTSMAA. Electrocardiographic analyses were done before and after PTSMAA, and the results were compared with the abnormal septal anatomy.Results: The effectiveness of PTSMAA was obtained in 18 (90%) of the 20 patients by ethanolization of the first great septal branch. In the other 2 patients (10%), 2 septal branches underwent alcoholization. First-grade temporary AV block (AVB) was observed in 6 patients (30%). Ten patients experienced severe bradycardia due to total AVB that required a temporary pacemaker, but 3 of the patients (15%) required a permanent pacemaker. Fourteen patients (70%) experienced permanent complete right branch block, and 2 developed incomplete left anterior block and incomplete left posterior block. Six patients presented with no electrical conduction disturbance at all.Conclusion: According to the results of the present investigation with the AV node artery derived from the right coronary artery in all cases, complete and permanent AV conduction system blockade occurred after PTSMAA in all types of anatomy regarding the observed LAD.

Nonsurgical septal reduction for hypertrophic obstructive cardiomyopathy: outcome in the first series of patients

BACKGROUND

Some patients with hypertrophic obstructive cardiomyopathy may gain symptomatic relief from a reduction in the extent of obstruction to left ventricular outflow. We present the outcome of the first series of patients treated with an alternative method of gradient reduction using catheter techniques.

METHODS AND RESULTS

Eighteen patients were treated with selective intracoronary alcohol injection to induce localized septal infarction. Patients underwent echocardiographic measurement of left ventricular dimensions and Doppler echocardiographic evaluation of left ventricular outflow tract gradients before the procedure, on the first postoperative day, and at a median follow-up of 3 months after the procedure. In addition, patients underwent exercise testing and symptom evaluation before and 3 months after nonsurgical septal reduction. There was a significant reduction in left ventricular outflow tract obstruction after the procedure (preprocedure, 67 mm Hg [95% CI, 48 to 87 mm Hg]; postprocedure, 25 mm Hg [95% CI, 16 to 34 mm Hg]; P=.0006), which persisted at 3-month follow-up (22 mm Hg [95% CI, 12 to 32 mm Hg]; P=.001). This was associated with a significant improvement in symptoms. There was a small but not significant increase in exercise capacity (n=10; preprocedure, 418 seconds [95% CI, 273 to 563 seconds]; postprocedure, 452 seconds [95% CI, 283 to 621 seconds). Left ventricular dimensions were not significantly altered by nonsurgical septal reduction.

CONCLUSIONS

Nonsurgical septal reduction significantly reduces left ventricular outflow tract obstruction and improves symptoms in some patients with hypertrophic obstructive cardiomyopathy. The technique may provide an alternative to surgical myomectomy in selected patients.

Non-surgical myocardial reduction for hypertrophic obstructive cardiomyopathy

Surgery has been the only therapeutic option in patients with hypertrophic obstructive cardiomyopathy who are resistant to drug treatment and sequential pacemaker therapy. I describe a novel catheter-based technique that may replace surgical myocardial reduction in some patients. The technique aims at selective destruction of the hypertrophied part of the left side of the intraventricular septum. If temporary occlusion of the first major septal artery is shown to reduce the intraventricular pressure gradient significantly, absolute alcohol is injected through the inflated balloon catheter to produce a localised infarct. In the first three patients treated with this method, the size of the septal infarct was sufficient to eliminate any subaortic stenosis immediately. Clinical improvement has been maintained up to 12 months. Non-surgical reduction of the septum in hypertrophic obstructive cardiomyopathy warrants further clinical evaluation.